code: def testBatch_Single(self):
      batched_state = state_util.batch(
          self._unbatched_states[0:1], batch_size=1
      )
      expected_batched_state = (
          np.array([[[1, 2, 3], [4, 5, 6]]]),
          (np.array([[7, 8]]), np.array([[9]])),
          np.array([[[10], [11]]]),
      )
  
      self._assert_sructures_equal(
          expected_batched_state, batched_state
      )
  
file_path: magenta/magenta/common/state_util_test.py
imports: from magenta.common import state_util
  import numpy
  import tensorflow.compat.v1
label_desc: Use image node_id 4 for calling the StateUtilTest obj's underlying member method code with example usage: obj.testBatch_Single() without return types